L-Theanine

Recovery/Sleep · Evidence: Moderate · Importance: Moderate

Supports relaxation and smoother stimulant experience; often paired with caffeine.

What the evidence says

Good evidence for reducing caffeine-related jitters and anxiety. Some sleep support.

Typical dose & timing

Dose: 100–200 mg

Timing: With caffeine pre-workout or evening for relaxation.

Role in a stack

Focus/stimulant smoothing or sleep support.

Redundancy check:

Cautions & safety

May cause drowsiness in some users.

Generally very well tolerated.

Best for

caffeine jitters · focus · calm energy · sleep routine

Buying guide

Budget: L-theanine capsules from a bulk brand. 100–200 mg per capsule is standard.

Standard: Quality L-theanine with Suntheanine branding — the most studied form.

Premium: Suntheanine third-party certified for competition use.

Source-verified products

Real products in this category, ordered by review count. Each price and rating comes from the product's own page, recorded 2026-07-29 — follow the link for current values. Links go to the product's source page and never affect this ranking.

• California Gold Nutrition L-Theanine (AlphaWave) 100 mg
  California Gold Nutrition · $12.99 · 4.7/5 (24535 ratings) · mid tier
• NOW Foods L-Theanine, 120 Veg Capsules
  NOW Foods · $11.01 · 4.7/5 (18221 ratings) · budget tier
• Nutricost L-Theanine 200 mg
  Nutricost · $11.01 · 4.8/5 (8964 ratings) · budget tier
• EVLution Nutrition L-Theanine 200 mg
  EVLution Nutrition · $11.93 · 4.7/5 (5040 ratings) · mid tier
• Doctor's Best L-Theanine 150 mg
  Doctor's Best · $20.99 · 4.6/5 (4652 ratings) · premium tier
• Life Extension L-Theanine 100 mg
  Life Extension · $18.00 · 4.8/5 (2512 ratings) · mid tier
• Sports Research L-Theanine 200 mg
  Sports Research · $25.97 · 4.7/5 (1622 ratings) · premium tier
• Force Factor L-Theanine 200 mg
  Force Factor · $8.42 · 4.8/5 (1462 ratings) · budget tier
• NaturesPlus Pro L-Theanine 200
  NaturesPlus · $8.42 · 4.8/5 (1407 ratings) · budget tier
• Micro Ingredients L-Theanine + Magnesium Glycinate
  Micro Ingredients · $20.97 · 4.8/5 (872 ratings) · mid tier
• Thorne Theanine 200 mg
  Thorne · $59.00 · 4.8/5 (677 ratings) · premium tier
• Vitamatic L-Theanine 200 mg
  Vitamatic · $20.99 · 4.6/5 (93 ratings) · premium tier

References

• L-theanine reduces psychological and physiological stress responses. Biological Psychology (2007)
  L-theanine reduces stress and anxiety responses. Consistent evidence for promoting relaxed alertness and reducing caffeine-related jitters when co-ingested with caffeine.